1. Field
The present invention generally relates to substrate process chambers and, more particularly, to tuning matching networks to match the impedance of a plurality of RF sources to a load within a substrate process chamber.
2. Description of the Related Art
Plasma enhanced substrate process chambers are widely used in the manufacture of integrated devices. In some plasma enhanced substrate process chambers, multiple radio frequency (RF) generators may be utilized to form and control the plasma. Each generator is connected to the substrate process chamber through a matching network. The matching network may be manually tuned and balanced for the percentage of power supplied by each generator. As a result of the manual tuning, significant trial and error substrate runs may be needed to further tune the match to minimize the reflected power. This manual trial and error process generally continues throughout processing to account for any drift in the chamber conditions. The currently used manual tuning is a slow and tedious process, reducing the efficiency of substrate processing.
Thus, the inventors have provided an improved method for tuning matching networks in substrate process chambers.